Gas steering and propulsion system for missiles



July 23, 1968 D. P. EASTMAN GAS STEERING AND PROPULSION SYSTEM FORMISSILES Filed Nov. 2, 1959 1N VEN TOR.

DAVID P. EASTMAN United States Patent 3,393,655 GAS STEERING ANDPROPULSION SYSTEM FOR MISSILES David P. Eastman, Novelty, Ohio, assignorto Clevite Corporation, Cleveland, Ohio, a corporation of Ohio FiledNov. 2, 1959, Ser. No. 851,216 5 Claims. (Cl. 114-20) This inventionpertains to a missile adapted to be employed in a fluid medium, and moreparticularly concerns a gas actuated steering control and a gas drivingmeans for the missile.

The invention may find application in underwater missiles such astorpedoes, decoys, target devices, training torpedoes and similarobjects.

An object of the invention is to provide a gas actuated steering controlfor an underwater missile.

Another object of the invention is to provide a gas driven underwatermissile.

Another object of the invention is to provide a gas driven missilehaving gas actuated steering controls wherein variations in the amountof gas consumed by the drive will not cause fluctuations in the steeringof the missile.

Still another object of the invention is to provide a missile which iscontrolled in elevation and in azimuth by gas actuated steering meanswherein the gas actuation of either the elevating mechanism or theazimuth mechanism does not establish a pressure fluctuation sufiicientto reflect to the other mechanism.

For a better understanding of the present invention, together with otherand further objects thereof, reference is had to the followingdescription taken in connection with the accompanying drawing, and itsscope will be pointed out in the appended claims.

An aspect of the present invention is an underwater missile comprising,a hull; gas means for propelling the hull through the water; a supply ofat least partly liquified gas within the hull at a temperaturesubstantially that of the water through which the hull is to bepropelled. Pressure and temperature reducing means are connected to thesupply of partly liquified gas and to a vaporizing means which, in turn,is connected to the gas means for propelling the hull, and at least aportion of the vaporizer means is in heat transfer relationship with thewater, whereby energy from the water is utilized to vaporize theliquefied gas and the latter is operably connected to propel the hull.Elevator means for controlling the dive and depth of the missile as itmoves through the water, includes a pendulum and bellows controlledvalve means. Rudder means control the missile in azimuth as it movesthrough the water, and include a gyro and a gyro controlled valve. Aconduit connects the vaporizer means to the gyro, to the gyro controlledvalve and to the pendulum and bellows controlled valve, whereby thepressure of the vaporized gas is regulated by the gyro controlled valveand by the pendulum and bellows controlled valve and is used to actuatethe elevator and the rudder.

FIGURE 1 is generally a schematic representation of the invention, withthe elevation control valve and azimuth controlled valve shown partiallyin section;

FIGURE 2 is an enlarged partly sectional view of the elevation controlvalve, similar as illustrated in FIG- URE 1.

With reference to FIGURE 1 there is shown a hull for a missile, such asa torpedo or similar devices. Within the hull there is positioned gascontrolled means for steering the hull in elevation and in azimuth withrespect to the medium in which it operates, and there is also mounted agas driven motor 11 for driving propellers 12, mounted outside the hull.

Disposed within the hull 10 is a storage tank 15 for gas such as COpreferably partly filled with liquid and partly filled with vapor. Theliquid and the vapor therein are in equilibrium and at a temperaturesubstantially the same as that of the sea water. Therefore, thecorrespond ing pressure within the tank will normally not exceed 900p.s.i. The tank may be loaded by means of a fill line 22.

Connected to the storage tank 15 is a valve mechanism 17, which servesseveral functions upon the firing or launching of the missile, ashereinafter further described.

A squib 18 is provided for rupturing a sealing disk 19 in the outletline 20 from the storage tank 15, thereby causing the liquefied orgaseous CO to flow through a sequence valve 25.

The squib 18 may be fired by the closing of a manually timed or pressureoperated switch 23 which connects a battery 24 to the squib, causing thesquib to fire and drive a hollow needle through the rupture disk 19.

The sequence valve 25 in its initial position, permits a stream of gasto flow at a line pressure of about 900 p.s.i. or less, into a gyroconduit 26 to a gyroscope 28, causing the gyroscope to become energized.Preferably, the supply of the fluid is taken from the bottom of thetank. This permits the removal of largely liquid from the tank wherebythe reduction of pressure therein is minimized. After the gyroscope isenergized the sequence valve 25 automatically shuts off the gas supplyto the gyro, and supplies gas through a pressure and temperatureregulating means 21 to conduit 29 and to the piston mechanism 30 whichuncages the gyro 28. A commercially available gyro may be utilized.

The pressure and temperature regulating means 21 may be comprised of,for instance, a spring loaded pressure regulating valve, or an orificeto maintain constant pressure within the vaporizer means over a widerange of ambient temperatures.

There is suflicient heat storage in the valve mechanism 17 and in theconduits 26, 29 leading to the gyro that liquid CO from the storage tankis gasified, only small quantities of the gas being needed to energizeand uncage the gyro.

Simultaneously with the uncaging of the gyro the gas or liquid, or both,flows through the pressure and temperature regulating means 21 to dropthe line pressure to about 400 p.s.i., at about 18 F. Thereafter thefluid is applied to a vaporizer means 35 such as an evaporator coilwhich is in heat transfer relationship with a heat supply. Thethermo-dynamie relationship gasifies any and all liquid and provides alarge volume of gas for driving the missile. Preferably the vaporizermeans comprises a double-walled section of the hull of the missile. Theouter skin of this section is in heat transfer relationship to the wateror other environment around the hull of the missile, and the liquefiedgas as it flows through the double-walled section absorbs largequantitles of heat from the environment, sufiicient to gasify andsuperheat all of the liquefied gas. Other means may be used to gasifythe liquid, such as passing the liquid through a coil in contact withthe environment as aforestated, or utilizing waste heat from somemechanism within the missile.

From the vaporizer means 35, the gas is applied through drive conduit 40to the engine for driving the propeller 12, or it is applied in smallquantities through conduit 41 to the steering means for the missile. Itis to be understood that when the gas is utilized only for driving themissile, other means must then be substituted to energize the steeringmechanism. Conversely, the gas may be applied solely for steeringmechanism purposes; or, the gas may be used simultaneously for drivingthe missile and for steering control.

A pressure reducing valve, or orifice 42 may be located in conduit 41 toprovide reduced pressure in conduit 46 for situations where the pressurerequirement of engine 11 is higher than suitable for use in the Steeringmechanism. However, to prevent interference between depth and azimuthsteering, the gas in conduit 46 should not be reduced below ahereinafter described limiting value.

The output line 46 from the pressure reducing valve 42 is split, part ofthe gas supply going through conduit 47 to the gyro controlled azimuth(rudder) valve means 50, providing in combination fixed spaceorientation means, and part going through conduit 48 to a pendulum andbellows controlled elevator means 67, (elevation control valve) forcontrolling the depth and dive of the missile in the water and providingtherewith a fixed depth orientation means.

In the gyro supply conduit 47 there is a pair of orifices, 51, 52,constituting a critical pressure drop, and the output conduits from theorifices 51, 52 are connected, respectively, to two rudder actuatingpistons 53, 54, which are connected in opposition to each other to thesteering rudder 55. A gyro controlled valve means 50 is connected to thetwo orifices 51, 52 and to the pistons 53, 54 in such a manner that whenthe missile is on its desired course a small amount of gas which is bledout of each of two bleed valves or ports 56, 57 experiences equalresistance to flow. This position being similar as illustrated inFIGURE 1. A valve body 58 is suitably connected to be controlled by thegyro 28 to maintain a fixed space orientation and is disposed within avalve sleeve 59. If the missile goes off its predetermined course, tothe right or to the left, the valve sleeve 59 which is rigidly connectedto the hull assumes a relative new position with respect to the gyrofixed valve body 58 thereby causing a change in the effective areas ofthe ports 56 (57). Consequently, the resistance to flow in the ports isvaried therewith and the pressure upon pistons 53, 54 is altered, oneincreasing and the other decreasing. The unequal pressures acting uponrudder 55 force the steering surface into a new position and the missilethereupon starts to turn back to its predetermined course. After themissile has responded to the new rudder position the valve sleeve 59gradually swings back to normal position, that is until the gas pressureis again equally applied to the two pistons 53, 54, and the missile isagain on its predetermined course.

The gas which exhausts from valves 56 and 57 passes through valve body58 into turbine buckets 33 of gyro 28 to keep it in rotation during therun.

From conduit 48 gas at about 85 psi. is applied to two pressure reducingorifices 61, 62 constituting the primary critical pressure drop, and thegas therefrom, at reduced pressure, is applied to two pistons 63, 64,and to the single elevation cpntrol valve 67. The pistons 63, 64 areconnected in opposition to an elevator 65 for controlling the depth ofthe missile in its surrounding medium, and the actuation of the pistons63, 64 is similar to the actuation of the pistons 53, 54.

The elevation of the missile is controlled by the elevation controlvalve 67 whose function is to control the diving rate and the depth ofthe missile by properly inducing the control surface 65 to act inaccordance with the pressure released by the up piston 63 and the downpiston 64. More particularly, the elevation control valve 67, shown indetail in FIGURE 2, comprises a hollow central shaft 69 adapted toreceive fluid through a bore 70. The fluid is admitted at both ends ofthe shaft 69 and prevented from intermixing by a partition wall (notshown) disposed near the center of the shaft between radial bores orports 71 and 73. The ports 71 and 73 are suitably spaced toindependently receive the gas so that any change in fluid pressure in aport may be individually reflected upon the respective up and downpistons 63, 64 which individually sense these changes. A concentricvalve sleeve 75 rotatably surrounds the central shaft 69 and portopenings 77 and '79 radially disposed therein are relatively movablewith respect to port openings 71 and 73 in the central shaft. Therelative position of the shaft port and the individual valve sleeve portis regulated by a lever 81 suitably attached to the sleeve 75 torotatably move the sleeve about the shaft 69. The sensing of the depthis accomplished by means of bellows 83 and 85 positioned on each side ofthe lever 81. The bellows 85 comprises preferably an air evacuatedcorrugated enclosure, providing pressure reference, suitably keptexpanded, for instance by means of expansion springs. The bellows 83 isstructurally similar, however oppositely disposed with respect tobellows 85. Bellows 83 is provided with a connection 24 to the watermedium in which the missile operates, filling the latter with water.

A pendulum valve portion 87 of the elevation control valve 67 compriseson one end a rotary valve body portion 89 positioned around a concentricvalve sleeve 75. Two hanging rods 91 extend therefrom to suspend weight92. The rotary valve body 89 forms a substantially elongated tubularstructure with arcuate portions thereof cut-out on one end 94 to allowlever 81 movements therebetween, and oppositely therefrom the rotaryvalve body forms a fiat surface 95, that is to say, a surface obtainedby shaving off a circular segment. Apertures or ports 97 and 99, one forup control the other for down, project through the flat plane radiallytoward the axial center of the shaft. The opposite end of the ports 97and 99 are exposed to the medium in which the missile operates and thusserve to discharge the fluid. When in operating condition, portions ofthe port 97 provide a communicating passageway to portions of the port77 of the concentric valve sleeve 75, and portions of the aperture 99provide similar passageway with portions of port 79. The ports 71, 73 ofthe shaft 69 ar aligned with the respective ports 77, 79.

To cause the missile to proceed at its predetermined depth the bellowsare adjusted so that the ports, after launching, assume a distortedangular position with respect to the valve body axis. Thus, the bellowsturn the gas discharge ports 77 (79) about an axis of rotation lying ina horizontal plane and on a line at right angle to the valve body axis.For example, the valve ports being correlated foot change in depth willcause a 2 turn of the port. Hence, if the unit is set for a six footdepth and launched at the surface of the water the ports 77 (79) areturned 12 with respect to their normal position. That is to say, theport 79 will be uncovered by the pendulum controlled valve and the port77 will be at least partially covered. The normal position is thatposition which is capable of maintaining a pressure equilibrium in thelines 66 and 68 and upon pistons 63 and 64. Consequently, in thatposition the ports 77 and 79 will be generally half open and halfclosed. Again, the angular port setting for depth will result in havingportions of the pendulum controlled valve body 89 cover the up elevatorport 79 therewith raising the pressure on piston or actuator 64 andproviding a downsteering movement through elevator 65. As the missiletilts downward toward the pre-set course, the water filled corrugatedbellows 83 starts to expand thereby moving the lever 81 attached tosleeve 75 to change the relative position of the ports. Thus, ports 77(79) swing slowly back to their normal position until the set depth hasbeen reached. When the missile is on course, or is in normal position,the openings of ports 77 (79) should be exactly equal and balance theforces upon the elevator. When the unit is lower than the predeterminedcourse, the up port 79 will be again at least partially covered by thependulum valve body 89 and the balance of forces on pistons 63 and 64will produce up elevator action. Thus, at a predetermined depth thependulum balances the pressures by effecting the opening of therespective ports to restore and maintain the missile at the pre-setlevel. It is thus the cooperative action between belows 83, 85 and thependulum controlled valve body 89 which produces the dive angle anddepth control.

In some missile applications a stopper 101 limiting the travel of thebellows may be desirable. The stopper prevents an unsuitable angularsetting of the ports with respect to the horizontal plane. For example,using the diving value of 'one foot of depth per 2 turn of port, adesired depth of thirty feet would correspondingly cause the bellowsupon hitting the water to turn the ports 60 with respect to thehorizontal plane, resulting in a diving angle harmful to stableperformance of the missile. The stopper, 101 (see FIGURE 2) is shownconnected to the bellows 83 and 85 abuts against the arm 81 to maintainthe ports in diving position at an angle desirable under thecircumstances.

The critical pressure drop at orifices 51, 52, 61, 62, prevents pressurefluctuations due to actuation of one control function, for exampleazimuth, from being reflected to the other control function, elevation.However, as aforestated, the pressure in conduit 46 should not bereduced below a limiting value.

The limiting value of pressure in conduit 46 is predicated upon theperformance of actuator means 53, 54, 63 and 64. In the steeringmechanism, the gas pressure is again reduced as aforestated to stilllower values of varying magnitude in the actuators, in accordance withsteering requirements. Fluctuations of pressure within the actuatorswill not reflect back into conduit 46 provided the minimum ratio ofabsolute pressures between conduit 46 and the actuators exceeds thecritical value for the particular gas in use. Thus, interference betweenseparate elements of the steering mechanism will be avoided if theabsolute pressure in conduit 46 is at least twice the maximum absolutepressure required in the actuators. A value of 85 to 100 p.s.i. inconduit 46 has been found convenient and effective.

The balancing of the system as heretofore described is based on awell-known principle of thremodynamics relating to the action oforifices which deliver gas from one region of pressure to another regionof lower pressure. This principle establishes the mass flow rate of gasthrough the orifice and shows this rate to be dependent upon the ratiobetween the low and high pressures. When the pressure on both sides ofthe orifice are equal, the pressure ratio is 1 and no gas will flow. Ifthe pressure on one side of the orifice is now reduced, the pressureratio will be less than 1 and a flow rate is established. This flow ratewill increase as the downstream pressure is reduced, or as the pressureratio is reduced, until a certain critical ratio is reached. Furtherreduction of the downstream pressure beyond this critical pressure willresult in no further increase in mass flow whatsoever.

The value of the critical pressure is dependent upon a finite propertyof a specific gas in use. Most gases, including the carbon dioxidesuggested for use in the steering system, ranges from .5 to .55. Thus,Whenever gas is delivered from one system to another through an orificeand the low pressure system operates at pressure equal to or less thanhalf the pressure of the delivery system, the orifice completelyisolates the high pressure system leaving both its pressure and massflow rate completely independent of pressure changes occurring in thelow pressure system.

The invention hereinbefore described is not restricted to anyconventional control surface arrangement, but the principle of theinvention may be utilized in connection with other control surfacearrangements, for instance, such as described and claimed in applicationfor Letters Patent, Ser. No. 827,663 filed July 16, 1959 and assigned tothe some assignee as the present invention.

While there have been described what are at present considered to be thepreferred embodiments of this invention, it will be obvious to thoseskilled in the art that various changes and modifications may be madetherein without departing from the invention, and it is, therefore,aimed in the appended claims to cover all such changes and modificationsas fall within the true spirit and scope of the invention.

I claim as my invention:

1. An underwater missile comprising, in combination:

a hull;

means for driving said hull through the water;

a storage tank within said hull for containing at least partly liquefiedfluid under pressure;

a steering system having elevator and rudder steering surfaces andincluding a plurality of fluid pressure responsive actuator means, eachactuator being effective to move one surface in one direction;

fixed space orientation means and fixed depth orientation means;

a main fluid supply conduit system connecting to said tank, said systemincluding at least one branch line connecting at least one actuator tosaid fixed depth orientation means, and another branch line connectingat least one other actuator to said fixed space orientation means;

both of said orientation means being constructed and arranged totranslate a deviation of the missile from its preset course into achange of fluid pressure in the respective branch line;

and orifice means in each of said branch lines having a suitable throatarea to pass fluids therethrough at a predetermined pressure drop toestablish a fluid pressure ratio within and between the main conduitsystem and each of the branch lines exceeding the critical value of saidfluid to avoid reflection of pressure changes between the branch lines.

2. An underwater missile comprising, in combination:

a hull;

means for driving said hull through the water;

a storage tank within said hull for containing at least partly liquefiedfluid under pressure;

a steering system having elevator and rudder steering surfaces andincluding a plurality of fluid pressure responsive actuator means, eachactuator being effective to move one surface in one direction;

fixed space orientation means and fixed depth orientation means;

a main fluid supply conduit system connecting to said tank, said systemincluding at least one branch line connecting at least one actuator tosaid fixed depth orientation means, and another branch line connectingat least one other actuator to said fixed space orientation means;

and a third branch line for feeding fluid to the means for driving saidhull;

both of said orientation means being constructed and arranged totranslate a deviation of the missile from its preset course into achange of fluid pressure in the respective branch line;

and orifice means in each of said branch lines having a suitable throatarea to pass fluids therethrough at a predetermined pressure drop toestablish a fluid pressure ratio within and between the main conduitsystem and each of the branch lines exceeding the critical value of saidfluid to avoid reflection of pressure changes between any one of thebranch lines.

3.hAlrI1 underwater missile comprising, in combination:

means for driving said hull through the water;

a storage tank within said hull containing at least partly liquefiedfluid under pressure;

a steering system having elevator and rudder steering surfaces andincluding a first and second fluid pressure responsive actuator meansconnected to said elevator surface, and a third and fourth fluidpressure responsive actuator mean-s connected to said rudder surface,each actuator being effective to move a surface in one direction;

fixed space orientation means and fixed depth orientation means;

a main fluid supply conduit system connecting to said tank, said systemincluding a first and a second branch line for connecting,independently, said first and second actuator to said fixed depthorientation means, and a third and fourth branch line for connecting,independently, said third and fourth actuator to said fixed spaceorientation means;

both of said orientation means being constructed and arranged totranslate a deviation of the missile from its preset course into achange of fluid pressure in the respective branch line;

orifice means in each of said branch lines having a suitable throat areato pass fluids therethrough at a predetermined pressure drop toestablish a fluid pressure ratio within and between the main conduitsystem and each of the branch lines exceeding the critical value of saidfluid to avoid reflection of pressure changes between the branch lines;

each pair of said actuator means including a bleeder valve elementadapted for controlling the fluid pressure.

4. A system according to claim 3 wherein a vaporizer is interposedbetween said tank and said orientation means to change the state of saidfluid.

5. A system according to claim 3 wherein said depth orientation meansincludes a bellows sensing device comprising a bellows exposed,normally, to sea water and a second bellows having an air evacuatedenclosure to provide a pressure reference relative to said first namedbellows.

References Cited UNITED STATES PATENTS FOREIGN PATENTS Great Britain.

BENJAMIN A. BORCHELT, Primary Examiner.

G. H. GLANZMAN, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,393,655 July 23, 1968 David P. Eastman It is certified that errorappears in the above identified patent and that said Letters Patent arehereby corrected as shown below:

Column 4, line 45, after "correlated" insert with the fluid pressure maybe so constructed that a one Signed and sealed this 27th day of January1970.

(SEAL) Attest:

Edward M. Fletcher, Jr. WILLIAM E. SCHUYLER, JR. l

Attesting Officer Commissioner of Patents I;

1. AN UNDERWATER MISSILE COMPRISING, IN COMBINATION: A HULL; MEANS FORDRIVING SAID HULL THROUGH THE WATER; A STORAGE TANK WITHIN SAID HULL FORCONTAINING AT LEAST PARTLY LIQUEFIED FLUID UNDER PRESSURE; A STEERINGSYSTEM HAVING ELEVATOR AND RUDDER STEERING SURFACES AND INCLUDING APLURALITY OF FLUID PRESSURE RESPONSIVE ACTUATOR MEANS, EACH ACTUATORBEING EFFECTIVE TO MOVE ONE SURFACE IN ONE DIRECTION; FIXED SPACEORIENTATION MEANS AND FIXED DEPTH ORIENTATION MEANS; A MAIN FLUID SUPPLYCONDUIT SYSTEM CONNECTING TO SAID TANK, SAID SYSTEM INCLUDING AT LEASTONE BRANCH LINE CONNECTING AT LEAST ONE ACTUATOR TO SAID FIXED DEPTHORIENTATION MEANS, AND ANOTHER BRANCH LINE CONNECTING AT LEAST ONE OTHERACTUATOR TO SAID FIXED SPACE ORIENTATION MEANS; BOTH OF SAID ORIENTATIONMEANS BEING CONSTRUCTED AND ARRANGED TO TRANSLATE A DEVIATION OF THEMISSILE FROM ITS PRESET COURSE INTO A CHANGE OF FLUID PRESSURE IN THERESPECTIVE BRANCH LINE; AND ORIFICE MEANS IN EACH OF SAID BRANCH LINESHAVING A SUITABLE THROAT AREA TO PASS FLUIDS THERETHROUGH AT APREDETERMINED PRESSURE DROP TO ESTABLISH A FLUID PRESSURE RATIO WITHINAND BETWEEN THE MAIN CONDUIT SYSTEM AND EACH OF THE BRANCH LINESEXCEEDING THE CRITICAL VALUE OF SAID FLUID TO AVOID REFLECTION OFPRESSURE CHANGES BETWEEN THE THE BRANCH LINES.